Electric cigar lighter



June 19, 1962 L. J. GAUDET ETAL 3,040,160

ELECTRIC CIGAR LIGHTER Filed July 1, 1959 v 2 Sheets-Sheet 1 INVENTORSAmy/awa d 63400:? 6 50565 fl 77035, J?

BY L m? 7 MM.

ATTORNEYS L. J. GAUDET El AL 3,040,160

ELECTRIC CIGAR LIGHTER June 19, 1962 Filed July 1, 1959 ZSheets-Sheet 2IN VENTORS BY M, fdzm ATTORNEYS United States Patent i 3,040,160ELECTRIC CIGAR LIGHTER Lawrence J. Gaudet and George A. Rose, Jr.,Meriden,

Conn., assignors, by mesne assignments, to American Machine & FoundryCompany, New York, N.Y., a

corporation of New Jersey Filed July 1, 1959, Ser. No. 824,237 9 Claims.(Cl. 219-32) This invention relates to electric cigar and cigarettelighters, and more particularly to cigar and cigarette lighters of thetype currently used in automobiles, motor boats, aircraft and the like.

The invention specifically relates to an improved lighter plug which maybe used in known types of cigar lighter plug sockets such as are shownin US. Patents 2,495,657, and 2,531,901.

One of the problems encountered in the use of cigar lighter plugs is theassembling of its various parts, and more particularly the securing ofthe plug carrier shell to the bushing which carries the knob. Presently,tabs or ears are provided on the metallic carrier shell which are, uponassembly, inserted into slots in the bushing and then bent or rolledover. This procedure is a rather slow operation and involves heavypressure. Care must be taken to assure secure joining of the elementsand to line up the tabs or ears of the carrier shell with slots providedin the bushing .element.

Another problem encountered in cigar lighter plugs now in use is that ofcurrent arcing internally in the socket wherein portions of the plug orsocket are damaged. A particular area of such arcing is between theheating unit cup and the thermostat of the socket, which by tougheningthe mating surfaces may have an adverse effect on the uniformity oftiming of the operation of the lighter.

It is, therefore, an object of the present invention to provide a cigarlighter plug which is simple in structure and easily assembled.

It is another object of the present invention to provide eflicient meansfor securing the knob carrying bushing to the plug carrier shell whichis free from rattles, and presents a very tight assembly.

It is a further object of the present invention to provide a cigarlighter plug which by its structure inherently cuts down the arcingbetween the heating unit and plug socket, and also provides for aninternal breaking of the electric circuit.

These and further objects and advantages will become readily apparent tothose skilled in the art upon consideration of the specification and theappended drawings in which:

FIGURE 1 is a longitudinal sectional view of an exemplary embodiment ofthe cigar lighter plug of the present invention;

FIGURE 2 is an end elevational view of the carrier shell and bushing ofthe cigar lighter plug in assembled position, looking from the righthand end of FIGURE 1 with the knob removed;

FIGURE 3 is a perspective view of a portion of the carrier shell andbushing with its flange removed;

.FIGURE 4 is an end View of the annular ground contact spring;

FIGURE 5 is a cross sectional view of the spring in FIGURE 4;

FIGURE 6 is a longitudinal sectional View of a modification on the cigarlighter plug of the present invention;

FIGURE 7 is a sectional view taken along line 77 of FIGURE 6;

FIGURE 8 is a longitudinal sectional view of the modification of FIGURE6 shown in a closed circuit position within a cigar lighter plug socket.

The preferred cigar lighter plug assembly of the present 0 3,040,160Patented June 19, 1962 "ice invention as shown in FIGURES 1-3 comprisesa substantially cylindrical plug shell 10 adapted for use in standardelectric cigar lighter sockets conventionally used in motor vehicles andthe like. The plug shell has an outwardly curled flange 12 at itsrearward end which cooperates with a cigar lighter socket (not shown),to limit the forward motion of the cigar lighter plug within the socket.The forward end of the plug shell 10 is provided with annular beads 14and 16 axially spaced and arranged for engagement with a spring frictionfinger provided in the wall of the socket (as schematically indicated atB in FIG. 8) so as to prevent accidental ejection of the plug. Disposedrearwardly from the annular bead 16 is an annular inwardly projectingrib 18. A heating element and carrier assembly indicated generally as 24is disposed within shell 10 and is adapted for axial movement therein.The assembly 24 comprises a ceramic heating element carrier 20 having anoutwardly extending integral flange 22 adapted to engage the rib 18 ofshell 10 and thereby limit the rearward axial movement of assembly 24within the shell. In the preferred embodiment the heating elementcarrier 20 is substantially disc-shaped, having a diameter substantiallyless than the diameter of integral flange 22, which is sufiicientlylarge to engage the interior wall of shell 10 and to engage the rib 18therein.

Suitably secured to the forward face of the heating unit carrier, as bythe customary stud 26, is a metallic heating element cup 28 which isinsulated from the stud 26 by mica washer 32 and encloses a heatingelement 30 which is preferably secured in the conventional manner bywelding its inner and outer ends to stud 26 and the inner wall'of cup28, respectively. This sub-assembly is secured to the closed end 34 ofcylindrical carrier shell 36 by means of the head 38 of stud 26.Interposed between the head 38 and the closed end 34 of the carriershell is a reinforcing washer 40. The rear face of the carrier 20 mayadvantageously have a slight concavity or depression 21 to ensure atight peripheral seat for shell 36.

Bushing 48 having flange 50 at the rearward end thereof is adapted to bedisposed within the rearward end of carrier shell 36 so that the flange50 engages the rearward end thereof upon assembly. The bushing isadapted as by socket 52 to accommodate a suitable knob 54. A pluralityof axially extending grooves 57, are formed for a purpose to be laterexplained, in the wall 49 of bushing 48 and are made accessible from therear face of the bushing by holes 56 which are aligned with them forthat purpose.

In assembly, the heating element carrier 20, heating element cup 28,heating element 30 and associated parts are connected to carrier shell36 as a sub-assembly. Bushing 48 is then placed open end down and thespring 46 is placed thereon with one end engaging the flange 50. Contactspring 42, provided with a plurality of inwardly projecting radially andaxially extending flexible fingers 44, is then placed on the other endof the spring 46 so that the fingers project toward flange '50 of thebushing 48. Plug shell 10 is then placed over the last mentionedassembly. The remainder of the sliding parts first assembled are thendropped into the open end of the plug shell, and pressure is appliedupon the cup 28 to secure the carrier shell to the bushing as describedbelow.

In order to secure the bushing 48 to carrier shell 36, lips 58 arestruck inwardly from the rearward edge of the carrier shell 36 adjacentthe flange 50 into each of the grooves 57, so that the lips 58 are bentinwardly over the bottoms 60 and edges of the grooves 57, firmlysecuring the bushing and carrier shell together.

The bushing and carrier shell may be readily and conveniently joined bya suitable tool including a plurality of small punches corresponding tothe number of axial grooves in the bushing. The tool is moved axially ofthe bushing so that each punch enters into each of the axial grooves inthe flange and bushing so that each punch engages a portion of therearward end of the carrier shell. Continued inward axial movement ofthe tool causes the punches .to strike a portion of the rearward end ofthe carrier shell inwardly over the bottom of each of the grooves so asto stretch the portion of the carrier shell engaged, and to deform it todefine a plurality of lips each conforming with a corresponding axialgroove. In actual practice it has been found most practical andefficient to employ punches having tapered diamond section tips.

In such a method of assembly little pressure is needed to strike thelips 58 of the shell inwardly over the edges of the grooves 57 in thebushing 48. The fact that the edges of the grooves serve as fulcrumsover which the metal is bent, together with the stretching of the lipsof the shell, makes a very tight assembly which is free from ratles andremarkably resistant to being pulled apart when compared with the smallpunch pressure involved. As indicated above, the customary procedure isto provide tabs or ears on the carrier shell and corresponding slots inthe bushing in order to secure the elements together. The operation ofbending or rolling the tabs or ears is .slow and involves rather heavyend pressure. In addi tion, assemblage in accordance with the presentinvention provides a blind assembly, leaving no metal parts exposed toconduct heat or current, and is tight with the use of very low endpressure. It should also be noted that the absence of ears or tabs inthe carrier shell makes for a lower cost shell and eliminates theproblem of aligning the tabs or cars with the slots in the bushing uponassembly.

The device illustrated in FIGURES 6-8 is a modification of the devicepreviously described, showing an alternative structure of the ceramicheating element carrier 70 and carrier shell 72. The modified heatingelement carrier 70 is substantially cylindrical and has an annularflange 74 near the forward end thereof to engage the interior wall ofplug shell 10 and engage the annular rib 18 thereof to limit therearward motion of the heating unit carrier Within the plug shell.Disposed rearwardly of the flange 74 is an axially extending tubularskirt 76 adapted to contact the flexible fingers 44 of ground contactspring 42 when the plug is in, or approaching open circuit position.Forward portion 78 of cylindrical carrier shell 72 is disposed withinthe tubular skirt 76 of the heating element carrier 70 and is securedthereto along with heating element cup 28 and heating element 30 by thestud 26 as previously described. The rearward end of carrier shell 72 isprovided with a step shoulder 80 which engages the rearward end of thetubular skirt 76 of heating element carrier 70. Cylindrical bushing 48is inserted within the step shoulder 80 of carrier shell 72 to seatagainst it, and the two are secured together by striking lips 58inwardly from the rearward end of carrier shell 72 as previouslydescribed above.

In approaching a closed circuit position heating element cup 28 engagesthe thermostat A of socket 90 before the circuit through the lighter iscompleted by the switching engagement of ground contact spring fingers44, with carrier shell 72. The circuit is broken by the separation offingers 44 and shell 72 before the separating of heating element cup 28and thermostat A. As the thermostat A serves as a spring detent and notas a positive latch, it is to some extent sprung open by a wedgingeffect of the cup 28 under the influence of spring 46 which results inthe cup .28 and thermostat A separating at some point on, or slightlypast, the equator of the cup.

It will thus be seen that the devices of the present invention haveovercome a serious problem in the assembling of the various componentsof cigar lighter plugs and also provide new and useful cigar lighterplugs which are economical and easily assembled. In assembling thedevices of the present invention in accordance with the method describedherein firmly secured, rattle free cigar lighter plugs are easilyconstructed.

In a plug as shown in FIGURE 1, the electn'cal path is through heatingunit cup 28, element 30, stud 26, washer 4i), and shell 36 to contactspring 42 and plug shell 10 which cooperates terminal-wise with the wallof socket (see FIGURE 8) and the heating unit cup 28 will similarlycooperate with thermostat A when pressed into contact therewith. Contactbetween cup 28 and thermostat A has a circuit controlling function whichresults in arcing between and roughening of the parts; this causesundesirable variations in timing and may be remedied by modification ofceramic unit carrier 20 and its associated carrier shell 36 as describedabove.

It will thus be seen that the objects of this invention have been fullyand eflectively accomplished. It should be realized, however, that theforegoing specific embodiments have been shown and described only forthe purpose of illustrating the principles of this invention and aresubject to extensive change without departure from such principles.Therefore, this invention includes all modifications encompassed withinthe spirit and scope of the following claims.

What is claimed is: I

1. A cigar lighter plug for use in an electric circuit comprising ametallic plug shell having an annular rib projecting inwardly therefrom,a heating element and carrier assembly adapted for axial movement withinsaid plug shell, said assembly including a carrier shell, a heatingelement carrier secured to the forward end of said carrier shell, and abushing mounted in the rearward end of said carrier shell, said bushinghaving a portion extending radially outwardly from the rearward endthereof, said bushing being grooved in an axial direction at.

a plurality of angularly spaced positions, and each groove being alignedwith an opening through said portion, lips struck inwardly from therearward edge of said carrier shell into said grooves securing thecarrier shell and bushing together, said carrier having an integralannular flange extending outwardly therefrom and adapted to engage theforward side of said plug shell rib, and spring means disposed betweenthe rearward side of said plug shell rib and the forward side of saidbushing flange adapted to urge said assembly rearwardly with respect tosaid shell, and an annular ground contact spring adapted to engage saidplug shell rib and said carrier shell.

2. A cigar lighter plug as defined in claim 1 wherein the electriccircuit is open and closed internally of said plug by the engagement anddis-engagement of said contact spring and said carrier shell.

3. A cigar lighter plug comprising a metallic plug shell, and a heatingelement and carrier assembly adapted for axial movement within said plugshell, said assembly including a carrier shell, a ceramic heatingelement carrier secured to the forward end of said carrier shell, and acylindrical bushing mounted in the rearward end of said carrier shell,said bushing having an annular flange extending outwardly from therearward end thereof, said bushing being grooved in axial direction at aplurality of angularly spaced positions, forward of said flange and eachgroove being aligned with an opening therethrough, and lips struckinwardly from the rearward edge of said carrier shell into said groovessecuring the carrier shell and bushing together.

4. A cigar lighter plug as defined in claim 3 wherein said heatingelement carrier is substantially disc-shaped.

5. A cigar lighter plug as defined in claim 3 wherein the rearward endof said heating element carrier is pro vided with an axially extendingtubular skirt adapted to receive the forward end of said carrier shell,said carrier shell having a step shoulder adapted to engage the rearwardend of said heating element carrier skirt and to seat said cylindricalbushing.

6. In an electric cigar lighter plug adapted for support on a holdingdevice having terminals for furnishing EMF. to an electrically resistantheating element carried by said plug at its forward end and having acontact for engagement with and separation from one of said terminals,said plug comprising a part movable relative to said holding device bymanual manipulation of a knob to move said contact into engagement withsaid one terminal, and also comprising knob support means secured tosaid movable part, the novel improvement wherein said movable part is ahollow metallic shell having a rim and being open at its rearward endfor embracingly receiving a first portion of said knob supporting means,a plurality of depressions in the embraced surface of said knobsupporting means wherein portions of the wall of said shell aredeflected into said depressions to interlock said knob supporting shelland said means, said means also comprising a second portion abuttingsaid rim and extending rearwardly and radially thereof and having a rearface, said second portion being so shaped as to permit passage of a toolaxially of said plug whereby portions of said wall may be deflectedradially inwardly into said depressions.

7. An electric cigar lighter plug adapted for support within a sockethaving terminals for furnishing to an electrically resistant heatingunit carried by said plug at its forward end and having terminals tocooperate with said first mentioned terminals, said plug comprising ahollow tongueless metallic member disposed rearwardly of said heatingunit and movable by manual manipulation of a knob comprehended by saidplug and attached thereto by knob supporting means having a firstportion at least in part peripherally within and embraced and engaged bysaid metallic member by distortion of a part thereof radially toward theaxis of said plug into a depression in the peripheral surface of saidfirst portion, said knob supporting means also having a second portionextending rearwardly and radially of said member and having a forwardface abutting the rear thereof for the transmittal of thrust thereto bymanipulation of said knob and being so shaped as to permit access by atool from the rear of said plug to a point forward of the rear of saidmember to eilect said distortion of said part thereof whereby saidembrace is tightened.

8. An electric cigar lighter plug assembly comprising a hollow metallicshell having an open rearward end and being arranged and adapted for theattachment and support of a heating unit at its forward end, said plugalso comprising knob supporting means having a first portion housedwithin said shell and affording a surface engaging the interior wallthereof and further having a second portion which in part abuts the rimof said open end of said shell and in part extends radially and axiallyrearwardly therebeyond, said first portion having a plurality ofdepressions in said surface which extend axially of said shell and saidsecond portion having discontinuities in alignment with said depressionswhereby access may be had thereto by a tool traversing axially of saidplug from the rear thereof to force lip-like deflections of said shellinto said depressions and thereby secure said shell and said knobsupporting means rigidly together.

9. in a cigar lighter plug of generally cylindrical form having aheating element adjacent its forward end and a knob at its rearmost endfor manipulation and movement of at least a part of said plug lyingaxially between said heating element and said knob when the plug issupported in an supplying holding device, the novel improvement of saidpart being a metallic shell, said knob being attached to said metallicshell by knob supporting means having a peripheral surface extendingaxially of the plug and embraced by said shell, said peripheral surfacehaving a depression into which a portion of said shell may be forced forinterlocking engagement and contracticn of said shell whereby itsembrace of said peripheral portion is tightened.

References Cited in the file of this patent UNITED STATES PATENTS2,329,844 Lehmann Sept. 21, 1943 2,727,976 Cone Dec. 20, 1955 2,727,977Penn Dec. 20, 1955 2,895,036 Ashton et al July 14, 1959

